Data transmission method and device

ABSTRACT

Embodiments of this application provide a data transmission method and a device. The method includes: obtaining, by a terminal, first indication information or second indication information, where the first indication information is used to indicate that a reference signal is carried in a resource unit, and the second indication information is used to indicate that no reference signal is carried in a resource unit; and performing, by the terminal, data transmission according to the first indication information or the second indication information. The reference signal can be properly configured in the embodiments.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Pat. Application No.17/385,599, filed on Jul. 26, 2021, which is a continuation of U.S. Pat.Application No. 16/146,537, filed on Sep. 28, 2018, now U.S. Pat. No.11,082,184, which is a continuation of International Application No.PCT/CN2017/095557, filed on Aug. 2, 2017, The International Applicationclaims priority to Chinese Patent Application No. 201610666714.5, filedon Aug. 12, 2016. All of the afore-mentioned patent applications arehereby incorporated by reference in their entireties.

TECHNICAL FIELD

Embodiments of this application relate to the field of communicationstechnologies, and in particular, to a data transmission method and adevice.

BACKGROUND

During data transmission in a wireless communications system, datareceived by a receiving end is usually different from data sent by atransmitting end due to a very complex propagation environment betweenthe transmitting end and the receiving end.

In order that the receiving end can restore the data sent by thetransmitting end, the transmitting end inserts a reference signal at afixed location of a resource unit during data transmission. Therefore,the receiving end can restore, based on the inserted reference signal,the data sent by the transmitting end.

In practice, in some cases, for example when the propagation environmentis relatively ideal, a reference signal may be inserted into a smallquantity of resource units to enable the receiving end to restore thedata sent by the transmitting end. However, the reference signal cannotbe flexibly configured in the manner of inserting a reference signal ata fixed location of a resource unit, thereby causing excessiveoverheads.

SUMMARY

Embodiments of this application provide a data transmission method and adevice, to resolve a problem that a reference signal cannot be flexiblyconfigured.

According to one aspect, an embodiment of this application provides adata transmission method, including obtaining, by a terminal, firstindication information or second indication information, where the firstindication information is used to indicate that a reference signal iscarried in a resource unit, and the second indication information isused to indicate that no reference signal is carried in a resource unit,for example, the terminal receives the first indication information orthe second indication information from a base station; and performing,by the terminal, data transmission according to the first indicationinformation or the second indication information. Optionally, thereference signal is used for at least phase noise cancellation. Theterminal may perform uplink data transmission or downlink datatransmission with the base station according to the first indicationinformation or the second indication information. Optionally, when theterminal performs downlink data transmission according to the firstindication information, the terminal performs phase noise cancellationbased on the reference signal. In a solution of this embodiment of thisapplication, the first indication information is used to indicate that areference signal is carried in a resource unit, and the secondindication information is used to indicate that no reference signal iscarried in a resource unit. Therefore, the reference signal is properlyconfigured, and this avoids a problem that overheads of the referencesignal are excessively large or reference signals are significantlyinsufficient, so that a process in which the terminal and the basestation perform data transmission according to the first indicationinformation or the second indication information is reliable.

In a possible design, that the terminal receives the first indicationinformation or the second indication information from a base stationincludes one of the following cases the terminal receives systeminformation from the base station, where the system information includesthe first indication information or the second indication information;the terminal receives a radio resource control (RRC) message from thebase station, where the RRC message includes the first indicationinformation or the second indication information; or the terminalreceives downlink control information (DCI) from the base station, wherethe DCI includes the first indication information or the secondindication information, and the system information may be a systeminformation block or a master information block.

Optionally, the first indication information or the second indicationinformation is carried in a first indication field.

Optionally, when the first indication information is carried in thefirst indication field, the system information, the RRC message, or theDCI further includes at least one of the following indication fields: asecond indication field, used to indicate an identifier of a referencesignal sequence; a third indication field, used to indicate atime-frequency resource location of the reference signal; or a fourthindication field, used to indicate a port identifier of the referencesignal.

Optionally, there is a correspondence between the port identifier of thereference signal and the identifier of the reference signal sequence. Inthis case, when the port identifier of the reference signal is obtained,the identifier of the reference signal sequence may be obtained based onthe correspondence, or when the identifier of the reference signalsequence is obtained, the port identifier of the reference signal may beobtained based on the correspondence.

By receiving the system information, the RRC message, or the downlinkcontrol information sent by the base station, the indication informationor configuration information is sent by using an existing message. Acommunication method does not need to be changed. Therefore, thisembodiment is compatible with the prior art, and is easy to operate andimplement.

In a possible design, the obtaining, by a terminal, first indicationinformation or second indication information includes: receiving, by theterminal, DCI from a base station, where the DCI includes informationabout a modulation order and/or information about a quantity ofscheduled resource blocks; and obtaining, by the terminal, the firstindication information or the second indication information based on theinformation about the modulation order and/or the information about thequantity of scheduled resource blocks. Specifically, when the modulationorder is greater than or equal to a preset modulation order and/or thequantity of scheduled resource blocks is greater than or equal to apreset quantity, the terminal may obtain the first indicationinformation; or when the modulation order is less than a presetmodulation order and/or the quantity of scheduled resource blocks isless than a preset quantity, the terminal may obtain the secondindication information. Because higher-order modulation is verysensitive to phase noise, and lower-order modulation is insensitive tophase noise, the reference signal for phase noise is not required whenthe modulation order is less than the preset modulation order. When thequantity of scheduled Resource Blocks (RBs) is greater than or equal tothe preset quantity, a gain brought by a phase noise pilot may begreater than a loss caused by overheads of the phase noise pilot.Therefore, when the quantity of scheduled RBs is greater than or equalto the preset quantity, the phase noise pilot may be inserted for phasenoise estimation.

In a possible design, the terminal may implicitly obtain theconfiguration information based on existing information. The followingpossible cases are specifically included:

In a possible case, the terminal obtains the configuration informationof the reference signal based on a correspondence between a cyclicredundancy check (CRC) mask of a physical broadcast channel (PBCH) andconfiguration information.

In another possible case, the terminal obtains the configurationinformation of the reference signal based on a correspondence between aphysical cell identifier and configuration information.

In a possible design, the terminal sends capability information of theterminal to the base station, and the capability information is used toindicate whether the terminal has a capability of canceling phase noise.The base station receives the capability information, and generates thefirst indication information or the second indication information basedon the capability information. The terminal sends the capabilityinformation to the base station. The base station generates the firstindication information or the second indication information based on thecapability information. Therefore, not only overheads of the phase noisepilot are reduced, but also it is ensured that downlink data finallyobtained by the terminal is not interfered by the phase noise.

In a possible design, the terminal sends a configuration request messageof a downlink reference signal to the base station. The configurationrequest message is used to request the base station to stop sending thedownlink reference signal, or is used to request the base station tosend the downlink reference signal. The base station receives theconfiguration request message, and the base station generates the firstindication information or the second indication information based on theconfiguration request message. The terminal sends the configurationrequest message to the base station. The base station generates theindication information based on the configuration request message.Therefore, not only overheads of the phase noise pilot are reduced, butalso it is ensured that downlink data finally obtained by the terminalis not interfered by the phase noise.

In a possible design, reference signals may be further classified into auser-level reference signal and a cell-level reference signal, to bespecific, a user-level phase noise pilot and a cell-level phase noisepilot. Optionally, for downlink data transmission, when a quantity ofterminals in a preset range is less than a first preset quantity, auser-level phase noise pilot is used; or when a quantity of terminals ina preset range is greater than a second preset quantity, a cell-levelphase noise pilot is used. The first preset quantity may be equal to thesecond preset quantity, or the first preset quantity may be less thanthe second preset quantity. The preset range may be a range covered by aphysical cell.

According to another aspect, this application provides another datatransmission method, including: sending, by a base station, firstindication information or second indication information to a terminal,where the first indication information is used to indicate that areference signal is carried in a resource unit, and the secondindication information is used to indicate that no reference signal iscarried in a resource unit; and performing, by the base station, datatransmission according to the first indication information or the secondindication information. Optionally, the reference signal is used for atleast phase noise cancellation. The base station may perform uplink datatransmission or downlink data transmission with the terminal accordingto the first indication information or the second indicationinformation. Optionally, when the base station performs uplink datatransmission according to the first indication information, the basestation performs phase noise cancellation based on the reference signal.In a solution of this embodiment, the first indication information isused to indicate that a reference signal is carried in a resource unit,and the second indication information is used to indicate that noreference signal is carried in a resource unit. Therefore, the referencesignal is properly configured, and this avoids a problem that overheadsof the reference signal are excessively large or reference signals aresignificantly insufficient, so that a process in which the terminal andthe base station perform data transmission according to the firstindication information or the second indication information is reliable.

In a possible design, the sending, by a base station, first indicationinformation or second indication information to a terminal includes oneof the following cases: sending, by the base station, system informationto the terminal, where the system information includes the firstindication information or the second indication information; sending, bythe base station, a radio resource control (RRC) message to theterminal, where the RRC message includes the first indicationinformation or the second indication information; or sending, by thebase station, downlink control information (DCI) to the terminal, wherethe DCI includes the first indication information or the secondindication information. For an indication field included in the systeminformation, the RRC message, and the DCI, refer to the foregoingdescription, and details are not described herein again.

According to still another aspect, an embodiment of this applicationprovides a terminal, and the terminal can implement functions executedby the terminal in the foregoing method embodiment. The functions may beimplemented by using hardware, or may be implemented by hardware byexecuting corresponding software. The hardware or the software includesone or more modules corresponding to the foregoing functions.

In a possible design, a structure of the terminal includes a processor,and a transmitter/receiver. The processor is configured to support theterminal in performing corresponding functions in the foregoing method.The transmitter/receiver is configured to support communication betweenthe terminal and a base station. The terminal may further include amemory. The memory is configured to be coupled to the processor. Thememory stores a program instruction and data of the terminal.

According to still another aspect, an embodiment of this applicationprovides a base station, and the base station can implement functionsexecuted by the base station in the foregoing method embodiment. Thefunctions may be implemented by using hardware, or may be implemented byhardware by executing corresponding software. The hardware or thesoftware includes one or more modules corresponding to the foregoingfunctions.

In a possible design, a structure of the base station includes aprocessor, and a transmitter/receiver. The processor is configured tosupport the base station in performing corresponding functions in theforegoing method. The transmitter/receiver is configured to supportcommunication between the base station and a terminal. The base stationmay further include a memory. The memory is configured to be coupled tothe processor. The memory stores a program instruction and data of thebase station.

According to still another aspect, an embodiment of this applicationprovides a communications system. The system includes the base stationand the terminal described in the foregoing aspects.

According to yet another aspect, an embodiment of this applicationprovides a computer storage medium, configured to store a computersoftware instruction used by the terminal. The computer softwareinstruction includes a related program used for executing the foregoingaspect.

According to yet another aspect, an embodiment of this applicationprovides a computer storage medium, configured to store a computersoftware instruction used by the base station. The computer softwareinstruction includes a related program used for executing the foregoingaspect.

In comparison with the prior art, in the solution provided in theembodiments of this application, the first indication information isused to indicate that a reference signal is carried in a resource unit,and the second indication information is used to indicate that noreference signal is carried in a resource unit. Therefore, the referencesignal is properly configured, and this avoids a problem that overheadsof the reference signal are excessively large or reference signals aresignificantly insufficient, so that a process in which the terminal andthe base station perform data transmission according to the firstindication information or the second indication information is reliable.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a possible applicable application scenario according to anembodiment of this application;

FIG. 2 shows a possible applicable network architecture according to anembodiment of this application;

FIG. 3 is a schematic flowchart of Embodiment 1 of a data transmissionmethod according to an embodiment of this application;

FIG. 4 is a signaling flowchart 1 of Embodiment 1 of a data transmissionmethod according to an embodiment of this application;

FIG. 5 is a signaling flowchart 2 of Embodiment 1 of a data transmissionmethod according to an embodiment of this application;

FIG. 6 is a signaling flowchart of Embodiment 2 of a data transmissionmethod according to an embodiment of this application;

FIG. 7 is a signaling flowchart of Embodiment 3 of a data transmissionmethod according to an embodiment of this application;

FIG. 8 is a signaling flowchart of Embodiment 4 of a data transmissionmethod according to an embodiment of this application;

FIG. 9 shows a possible schematic structural diagram of a relatedterminal according to an embodiment of this application;

FIG. 10 shows another possible schematic structural diagram of a relatedterminal according to an embodiment of this application;

FIG. 11 shows a possible schematic structural diagram of a related basestation according to an embodiment of this application; and

FIG. 12 shows another possible schematic structural diagram of a relatedbase station according to an embodiment of this application.

DESCRIPTION OF EMBODIMENTS

The following describes the technical solutions in the embodiments ofthis application with reference to the accompanying drawings in theembodiments of this application.

A network architecture and a service scenario described in theembodiments of this application are intended to more clearly describethe technical solutions in the embodiments of this application, and donot constitute a limitation on the technical solutions provided in theembodiments of this application. Persons of ordinary skill in the artmay learn that, with evolution of the network architecture and emergenceof a new service scenario, the technical solutions provided in theembodiments of this application are applicable to similar technicalproblems.

The following first describes a possible application scenario andnetwork architecture in the embodiments of this application withreference to FIG. 1 and FIG. 2 .

FIG. 1 shows a possible applicable application scenario according to anembodiment of this application. As shown in FIG. 1 , a terminal accessesan operator Internet Protocol (IP) service network such as a IPmultimedia subsystem (IMS) network or a packet switched streamingservice (PSS) network by using a radio access network (RAN) and a corenetwork (CN). The technical solutions described in this application maybe applied to a Long Term Evolution (LTE) system, or other wirelesscommunications systems of various radio access technologies, forexample, a system using an access technology such as Code DivisionMultiple Access (CDMA), Frequency Division Multiple Access (FDMA), TimeDivision Multiple Access (TDMA), orthogonal frequency division multipleaccess OFDMA), or a single carrier frequency division multiple access(SC-FDMA). In addition, the technical solutions may further be appliedto a subsequent evolved system of the LTE system, for example, a 5thGeneration (5G) system. For clarity, only the LTE system is used as anexample herein for description. In the LTE system, an evolved universalterrestrial radio access network (E-UTRAN) is used as a radio accessnetwork, and an evolved packet core (EPC) is used as a core network. Theterminal accesses an IMS network by using the E-UTRAN and the EPC. Itshould be noted that a name of the base station and a name of theterminal may change when the solutions in the embodiments of thisapplication are applied to the 5G system or another system that mayoccur in the future, but this does not affect implementation of thesolutions in the embodiments of this application.

In the embodiments of this application, a noun “network” and a noun“system” are usually used alternately, but persons skilled in the artmay understand a meaning. A terminal related to the embodiments of thisapplication may include a handheld device, an in-vehicle device, awearable device, or a computing device that has a wireless communicationfunction; another processing device connected to a wireless modem; oruser equipment (UE) in various forms including a mobile station (MS), aterminal device, and the like. For ease of description, the devicesmentioned above are collectively referred to as a terminal. A basestation (BS) related to the embodiments of this application is anapparatus that is deployed in a radio access network and that isconfigured to provide a wireless communication function for a terminal.The base station may include a macro base station, a micro base station,a relay node, an access point, and the like in various forms. In systemsusing different radio access technologies, names of devices having afunction of a base station may vary. For example, the device is referredto as an evolved NodeB (eNB or eNodeB) in a Long Term Evolution (LTE)system, or referred to as a NodeB in a 3G communications system. Forease of description, in the embodiments of this application, all theforegoing apparatuses that provide a wireless communications functionfor the terminal are referred to as a base station or a BS.

In the application scenario shown in FIG. 1 , FIG. 2 shows a possibleapplicable network architecture according to an embodiment of thisapplication. The network architecture mainly includes a base station 01and a terminal 02. Wireless communication is performed between the basestation 01 and the terminal 02.

The following further describes the embodiments of this application indetail based on common aspects mentioned in the foregoing embodiments ofthis application.

In an existing solution, when data transmission is performed between abase station and a terminal, a reference signal is fixedly inserted intoa resource unit. In this way, a receiving end of data performs channelestimation, channel detection, phase noise estimation, and the likebased on the reference signal, to restore the data sent by atransmitting end. The resource unit refers to a time-frequency resourceunit used to carry data, for example, one or more resource blocks (RB)or one or more resource block groups (RBG). For example, during downlinkdata transmission, the base station inserts a downlink reference signalinto the resource unit, and when receiving a downlink signal thatincludes the downlink reference signal, the terminal may perform channelestimation, channel detection, phase noise estimation, and the likebased on the downlink reference signal, to restore downlink data.Similarly, in uplink data transmission, the base station may alsorestore uplink data based on an uplink reference signal.

However, in the existing solution of inserting a reference signal at afixed location of a resource unit, the reference signal cannot beflexibly configured. As a result, in practice, overheads of thereference signal may be excessively large, or inserted reference signalsare significantly insufficient, and consequently a requirement of anactual propagation environment cannot be met.

In view of this, an embodiment provides a data transmission method, toproperly configure a reference signal. It should be noted that, in thisembodiment of this application, the related reference signal may be usedfor at least one of channel estimation, channel detection, frequencyoffset estimation, phase noise estimation, or phase noise cancellation.Alternatively, the reference signal may be a reference signal speciallyused for channel estimation, a reference signal specially used forchannel detection, a reference signal specially used for phase noiseestimation, or a reference signal specially used for phase noisecancellation. The reference signal specially used for phase noisecancellation or a reference signal at least used for phase noisecancellation may also be referred to as a phase noise pilot. For ease ofdescription, in methods shown in FIG. 3 to FIG. 8 , the embodiments ofthis application are described by using a phase noise pilot as anexample.

Specifically, for the phase noise pilot, in a wireless communicationssystem, because a frequency processing component of a transmitting endis not ideal, an output carrier signal is not pure, and may carry phasenoise. In a future evolved wireless system of the 3^(rd) GenerationPartnership Project (3GPP), a used spectrum includes high frequency.Therefore, to resolve phase noise generated due to high frequency, areceiving end uses the phase noise pilot to estimate the phase noise,and then compensates for impact of the phase noise to eliminate thephase noise.

FIG. 3 is a schematic flowchart of Embodiment 1 of a data transmissionmethod according to an embodiment of this application. As shown in FIG.3 , the method includes:

S301. A terminal obtains first indication information or secondindication information, where the first indication information is usedto indicate that a reference signal is carried in a resource unit, andthe second indication information is used to indicate that no referencesignal is carried in a resource unit.

S302. The terminal performs data transmission according to the firstindication information or the second indication information.

The terminal in this embodiment obtains different indication informationindicating whether a reference signal is carried in a resource unit. Theindication information may be information predefined in a system, or maybe indication information received by the terminal from a base station,or may be indication information received by the terminal from anothernetwork element. The reference signal may be an uplink reference signalor a downlink reference signal.

In an example, the first indication information or the second indicationinformation may be carried in an information element. When theinformation element carries the first indication information, itindicates that a reference signal is carried in a resource unit. Whenthe information element carries the second indication information, itindicates that no reference signal is carried in a resource unit. Thatis, in this case, the information element may be used to indicatewhether a reference signal is carried in a resource unit.

Optionally, in this embodiment, when at least one of the followingconditions is met, a reference signal needs to be carried in a resourceunit. The at least one of the following conditions is specifically: Theterminal or the base station has a capability of canceling phase noise;a modulation order of a modulation and coding scheme (MCS) used in thesystem is greater than or equal to a preset modulation order; or aquantity of scheduled resource blocks is greater than or equal to apreset quantity.

Correspondingly, when at least one of following conditions is met, noreference signal is carried in a resource unit. The at least one of thefollowing conditions is specifically: The terminal or the base stationdoes not have a capability of canceling phase noise; a modulation orderof an MCS used in the system is less than a preset modulation order; ora quantity of scheduled resource blocks is less than a preset quantity.In this case, when the reference signal is not required during phasenoise estimation, the reference signal is not inserted into the resourceunit, thereby reducing overheads of the reference signal.

Persons skilled in the art may understand that higher-order modulationis very sensitive to phase noise, and lower-order modulation isinsensitive to phase noise. When the quantity of scheduled RBs isgreater than or equal to the preset quantity, a gain brought by a phasenoise pilot may be greater than a loss caused by overheads of the phasenoise pilot; or when the quantity of scheduled RBs is less than thepreset quantity, a gain brought by a phase noise pilot may be less thana loss caused by overheads of the phase noise pilot.

In an example, when the terminal obtains the first indicationinformation, the terminal may obtain configuration information. Theconfiguration information includes the first indication information. Theconfiguration information further includes time-frequency resourcelocation information of the reference signal, port information of thereference signal, or sequence information of the reference signal.

Specifically, the terminal may obtain the configuration information in apredefined manner, may receive the configuration information from thebase station, or may obtain the configuration information from otherinformation sent by the base station. A specific implementation in whichthe terminal obtains the configuration information is not limited hereinin this embodiment.

The time-frequency resource location information of the reference signalincludes a time-frequency resource location of the reference signal, ormay include a location type of a time-frequency resource of thereference signal, to be specific, each location type corresponds to atime-frequency resource location. The time-frequency resource locationmay be a location of the reference signal in time domain and/orfrequency domain. In an optional embodiment, the reference signaloccupies one or more subcarriers. Correspondingly, the time-frequencyresource location of the reference signal may be a location of ascheduled subcarrier of the reference signal in frequency domain.

The sequence information of the reference signal includes a referencesignal sequence; or may include an identifier of a reference signalsequence, where there is a correspondence between the identifier of thereference signal sequence and the reference signal sequence.

The port information of the reference signal includes an identifier of aport of the reference signal. The port of the reference signal isspecifically an antenna port, and the identifier may be specifically aport number. The antenna port is configured to distinguish betweenresources in space, and different reference signals may be transmittedon different antenna ports.

Specifically, when a reference signal is carried in a resource unit, theterminal obtains the first indication information. The first indicationinformation is used to indicate that a reference signal is carried in aresource unit. Data transmission may be performed between the basestation and the terminal according to the first indication information.The data transmission includes uplink data transmission and downlinkdata transmission.

In an example, when the reference signal is a downlink reference signal,the terminal and the base station perform downlink data transmissionaccording to the first indication information. Correspondingly, theterminal may perform phase noise cancellation based on the downlinkreference signal, and a specific process may be shown in FIG. 4 . Whenthe reference signal is an uplink reference signal, the base station andthe terminal perform uplink data transmission according to the firstindication information. Correspondingly, the base station may performphase noise cancellation based on the uplink reference signal, and aspecific process may be shown in FIG. 5 .

In methods shown in FIG. 4 and FIG. 5 , an example in which the terminalreceives the first indication information from the base station is usedfor description.

FIG. 4 is a signaling flowchart 1 of Embodiment 1 of a data transmissionmethod according to an embodiment of this application. FIG. 4 mainlydescribes a downlink data transmission process between a base stationand a terminal. As shown in FIG. 4 , the method includes:

S401. The base station sends first indication information to theterminal.

The first indication information is used to indicate that a downlinkreference signal is carried in a resource unit.

S402. The base station inserts a downlink reference signal into aresource unit.

S403. The base station and the terminal perform downlink datatransmission.

S404. The terminal performs phase noise cancellation based on thedownlink reference signal.

S402 to S404 are a process in which the base station and the terminalperform downlink data transmission according to the first indicationinformation. It should be noted that S404 is an optional step.

FIG. 5 is a signaling flowchart 2 of Embodiment 1 of a data transmissionmethod according to an embodiment of this application. FIG. 5 mainlydescribes an uplink data transmission process of a base station and aterminal. As shown in FIG. 5 , the method includes:

S501. The base station sends first indication information to theterminal.

The first indication information is used to indicate that an uplinkreference signal is carried in a resource unit.

S502. The terminal inserts an uplink reference signal into a resourceunit.

S503. The base station and the terminal perform uplink datatransmission.

S504. The base station performs phase noise cancellation based on theuplink reference signal.

S502 to S504 are a process in which the base station and the terminalperform uplink data transmission according to the first indicationinformation. It should be noted that S504 is an optional step.

When no reference signal is carried in a resource unit, the terminalobtains second indication information. The second indication informationis used to indicate that no reference signal is carried in a resourceunit. The base station and the terminal may perform data transmissionbased on the second indication information. The data transmissionincludes uplink data transmission and downlink data transmission. Inthis case, in a downlink data transmission process, the base stationdoes not insert a phase noise pilot into the resource unit; and afterreceiving a downlink signal, the terminal does not perform a phase noisecancellation operation. In an uplink data transmission process, theterminal does not insert a phase noise pilot into the resource unit; andafter receiving an uplink signal, the base station does not perform aphase noise cancellation operation. In this case, the phase noise pilotdoes not need to be inserted into the resource unit, so as to reducetransmission overheads. In addition, the base station or the terminalmay not need to perform a phase noise cancellation operation, so as tosimplify an operation of the base station or the terminal.

According to the data transmission method provided in this embodiment,the terminal obtains the first indication information or the secondindication information. The first indication information is used toindicate that a reference signal is carried in a resource unit, and thesecond indication information is used to indicate that no referencesignal is carried in a resource unit. Therefore, the reference signal isproperly configured, and this avoids a problem that overheads of thereference signal are excessively large or reference signals aresignificantly insufficient, so that a process in which the terminal andthe base station perform data transmission according to the firstindication information or the second indication information is reliable.

For the first indication information, the second indication information,or the configuration information in the foregoing embodiments, thefollowing uses an example to describe a specific implementation in whichthe terminal obtains the first indication information, the secondindication information, or the configuration information. Personsskilled in the art may understand that the first indication information,the second indication information, or the configuration information inthe following may be first indication information, second indicationinformation, or configuration information for downlink datatransmission; or may be first indication information, second indicationinformation, or configuration information for uplink data transmission.Refer to FIG. 5 for application of the first indication information, thesecond indication information, or the configuration information in theuplink data transmission process. Refer to FIG. 4 for application of thefirst indication information, the second indication information, or theconfiguration information in the downlink data transmission process.Details are not described herein again in this embodiment.

In a specific embodiment, the base station may include the firstindication information or the second indication information in anothermessage sent to the terminal. The following feasible implementations maybe specifically included:

In a feasible implementation, the base station sends system informationto the terminal, and the terminal receives the system information fromthe base station, where the system information includes the firstindication information or the second indication information. It shouldbe noted that the system information may be specifically a systeminformation block (SIB), or may be a master information block (MIB).

In another feasible implementation, the base station sends a radioresource control (RRC) message to the terminal, and the terminalreceives the RRC message from the base station, where the RRC messageincludes the first indication information or the second indicationinformation.

In still another feasible implementation, the base station sendsdownlink control information (DCI) to the terminal, and the terminalreceives the DCI from the base station, where the DCI includes the firstindication information or the second indication information.

Based on the foregoing feasible implementations, a first indicationfield is set in the system information, the RRC message, or the DCI. Thefirst indication information or the second indication information iscarried in the first indication field. Specifically, the firstindication field may be 1 bit. For example, 1 indicates that a phasenoise pilot is inserted into a resource unit, and 0 indicates that nophase noise pilot is inserted into a resource unit; or 1 indicates thatno phase noise pilot is inserted into a resource unit, and 0 indicatesthat a phase noise pilot is inserted into a resource unit.

Optionally, when the first indication information is carried in thefirst indication field, the system information, the RRC message, or theDCI further includes at least one of the following indication fields:

-   a second indication field, used to indicate an identifier of a    reference signal sequence, where the identifier of the reference    signal sequence may be, for example, an index of the reference    signal sequence;-   a third indication field, used to indicate a time-frequency resource    location of a reference signal, where the time-frequency resource    location of the reference signal may be indicated by using type    information of the reference signal, for example, different types of    reference signals correspond to different locations; or-   a fourth indication field, used to indicate a port identifier of the    reference signal, where the port identifier of the reference signal    may be, for example, an index of a port of the reference signal.

The indication fields are separately described in the following by usingexamples.

The second indication field is used to indicate the identifier of thereference signal sequence. Specifically, the identifier of the referencesignal sequence may be, for example, 1, 2, or 3. If there are N (N is anatural number) reference signal sequences, log₂ N bits are used toindicate an identifier of a reference signal sequence.

The third indication field is used to indicate the time-frequencyresource location of the reference signal. Specifically, it may bepredefined that there are N (N is a natural number) types oftime-frequency resource locations of reference signals. Each locationtype corresponds to a specific time-frequency resource location, andlog₂ N bits are used to indicate a location type of a time-frequencyresource.

The fourth indication field is used to indicate the port identifier ofthe reference signal. Further, there is a correspondence between theport identifier of the reference signal and the identifier of thereference signal sequence. In this case, when the port identifier of thereference signal is obtained, the identifier of the reference signalsequence may be obtained based on the correspondence, or when theidentifier of the reference signal sequence is obtained, the portidentifier of the reference signal may be obtained based on thecorrespondence. Table 1 shows a feasible correspondence.

TABLE 1 Identifier of a reference signal sequence Reference signalsequence Port identifier of a reference signal 1 1, 1, 1, 1, 1, 1, 1, 17 2 1, 1, -1, -1, 1, 1, -1, -1 8 3 1, -1, 1, -1, 1, -1, 1, -1 9 4 1, -1,-1, 1, 1, -1, -1, 1 10

In this embodiment, the base station sends the system information, theRRC message, or the downlink control information to the terminal. Theindication information or the configuration information is sent by usingan existing message, and a communication method does not need to bechanged. Therefore, this embodiment is compatible with the prior art,and is easy to operate and implement.

In another specific embodiment, based on the embodiment of FIG. 3 , theterminal may further obtain the first indication information or thesecond indication information based on information included in thedownlink control information. The following provides detaileddescription with reference to FIG. 6 .

FIG. 6 is a signaling flowchart of Embodiment 2 of a data transmissionmethod according to an embodiment of this application. As shown in FIG.6 , the method includes:

S601. A base station sends DCI to a terminal.

The DCI includes information about a modulation order and/or informationabout a quantity of scheduled resource blocks.

S602. The terminal obtains first indication information or secondindication information based on information about a modulation orderand/or information about a quantity of scheduled resource blocks.

The DCI information includes at least the following content elements:resource block allocation information, and a modulation and codingscheme (MCS). The resource block allocation information includes thequantity of scheduled resource blocks. The MCS includes the modulationorder. The modulation order includes 2, 4, and 6. There is acorrespondence between a modulation mode and a modulation order. Forexample, quadriphase shift keying (QPSK) corresponds to a modulationorder 2, 16 quadrature amplitude modulation (QAM) corresponds to amodulation order 4, and 64QAM corresponds to a modulation order 6.

Specifically, the terminal may obtain the first indication informationby using the following feasible implementations:

In a feasible implementation, when the modulation order is greater thanor equal to a preset modulation order, the terminal obtains the firstindication information.

In another feasible implementation, when the quantity of scheduledresource blocks is greater than or equal to a preset quantity, theterminal obtains the first indication information.

In still another feasible implementation, when the modulation order isgreater than or equal to a preset modulation order, and the quantity ofscheduled resource blocks is greater than or equal to a preset quantity,the terminal obtains the first indication information.

Correspondingly, the terminal may obtain the second indicationinformation by using the following feasible implementations:

In a feasible implementation, when the modulation order is less than apreset modulation order, the terminal obtains the second indicationinformation.

In another feasible implementation, when the quantity of scheduledresource blocks is less than a preset quantity, the terminal obtains thesecond indication information.

In still another feasible implementation, when the modulation order isless than a preset modulation order, and the quantity of scheduledresource blocks is less than a preset quantity, the terminal obtains thesecond indication information.

Optionally, the preset modulation order for the modulation order and thepreset quantity for the quantity of scheduled RBs may be a default orderor quantity in the system or may be predefined in the system, or may besent by the base station to the terminal in advance by using variousmessages or signaling.

Persons skilled in the art may understand that when the terminal obtainsthe indication information based on the downlink control information,and when the base station sends system information, an RRC message, orthe downlink control information to the terminal, a first indicationfield does not need to be set in an indication field of each piece ofinformation.

In this embodiment, the terminal implicitly obtains the first indicationinformation or the second indication information by using the downlinkcontrol information. There is no need to independently send information,existing information is unchanged, and no new information is added.Therefore, a process in which the terminal obtains the indicationinformation is simple and easy to implement.

In a still another specific embodiment, the terminal may implicitlyobtain configuration information based on existing information. Thefollowing possible cases are specifically included:

In a possible case, the terminal obtains the configuration informationof the reference signal based on a correspondence between a cyclicredundancy check (CRC) mask of a physical broadcast channel (PBCH) andconfiguration information.

Specifically, a broadcast channel (BCH) is mapped to the PBCH afterundergoing CRC, rate matching and channel coding, CRC mask scrambling,and antenna mapping. Correspondingly, after receiving the PBCH, theterminal needs to obtain the BCH through demapping, descrambling,reverse CRC, and the like. After the descrambling, the terminal mayobtain the CRC mask. In this embodiment, there is a presetcorrespondence between a CRC mask and configuration information.Optionally, the CRC mask may indicate whether a reference signal iscarried in a subframe. Different CRC masks correspond to differentreference signal sequences, different CRC masks correspond to differenttime-frequency resource locations of reference signals, and differentCRC masks correspond to different ports of reference signals.

In another possible case, the terminal obtains the configurationinformation of the reference signal based on a correspondence between aphysical cell identifier and configuration information.

Specifically, there are 504 physical cell identifiers (PCI) in an LTEsystem. The terminal searches for a primary synchronization signal (PSS)and a secondary synchronization signal (SSS), and combines the twosignals to determine a specific physical cell identifier. Optionally,the physical cell identifier may correspondingly indicate whether areference signal is carried in a subframe. When the physical cellidentifier is a number identifier, modulo processing may be performed onthe physical cell identifier based on a quantity of reference signalsequences, and different modulo results correspond to differentreference signal sequences; or modulo processing may be performed on thephysical cell identifier based on a quantity of location types oftime-frequency resources, and different modulo results correspond todifferent time-frequency resource locations.

In this embodiment, the configuration information is determined based onthe CRC mask or the physical cell identifier. There is no need toindependently send information, existing information is unchanged, andno new information is added. Therefore, a process in which the terminalobtains the configuration information is simple and easy to implement.

Based on the foregoing embodiment, in an application scenario in whichthe base station sends downlink data to the terminal, the terminal mayfurther send a configuration indication to the base station, so that thebase station can generate indication information of a downlink referencesignal. Implementations shown in FIG. 7 and FIG. 8 may be specificallyincluded.

FIG. 7 is a signaling flowchart of Embodiment 3 of a data transmissionmethod according to an embodiment of this application. The methodincludes:

S701. A terminal sends capability information of the terminal to a basestation.

The capability information is used to indicate whether the terminal hasa capability of canceling phase noise.

S702. The base station generates first indication information or secondindication information based on the capability information of theterminal.

Specifically, the terminal may directly send the capability informationto the base station; or the capability information may be carried in anRRC message sent by the terminal to the base station, or may be carriedin another message. The capability information is specifically used toindicate whether the terminal has a capability of canceling phase noise.

After receiving the capability information, the base station generatesconfiguration information based on the capability information, that is,whether the base station needs to insert a reference signal into adownlink resource unit.

When the capability information is used to indicate that the terminaldoes not have the capability of canceling phase noise, the base stationgenerates the second indication information.

When the capability information is used to indicate that the terminalhas the capability of canceling phase noise, the base station generatesthe first indication information.

In this embodiment, the terminal sends the capability information to thebase station. The base station generates the first indicationinformation or the second indication information based on the capabilityinformation. Therefore, not only overheads of a phase noise pilot arereduced, but also it is ensured that downlink data finally obtained bythe terminal is not interfered by phase noise.

FIG. 8 is a signaling flowchart of Embodiment 4 of a data transmissionmethod according to an embodiment of this application. The methodincludes:

S801. A terminal sends a configuration request message of a downlinkreference signal to a base station.

The configuration request message is used to request the base station tostop sending the downlink reference signal, or is used to request thebase station to send the downlink reference signal.

S802. The base station generates first indication information or secondindication information based on the configuration request message.

Specifically, the terminal may send the configuration request message ofthe downlink reference signal to the base station based on ademodulation result of downlink data. Specifically, if there isrelatively large phase noise interference in the demodulation result,the configuration request message is used to request the base station tosend the downlink reference signal. If there is no phase noiseinterference in the demodulation result, the configuration requestmessage is used to request the base station to stop sending the downlinkreference signal.

After receiving the configuration request message of the downlinkreference signal that is sent by the terminal, the base stationgenerates the indication information based on the configuration requestmessage. Specifically, if the configuration request message is used torequest the base station to send the downlink reference signal, the basestation generates the first indication information. If the configurationrequest message is used to request the base station not to send thedownlink reference signal, the base station generates the secondindication information.

In this embodiment, the terminal sends the configuration request messageto the base station. The base station generates the indicationinformation based on the configuration request message. Therefore, notonly overheads of a phase noise pilot are reduced, but also it isensured that downlink data finally obtained by the terminal is notinterfered by phase noise.

Based on the foregoing embodiment, reference signals provided in thisembodiment may further be classified into a user-level reference signaland a cell-level reference signal, to be specific, a user-level phasenoise pilot and a cell-level phase noise pilot. The user-level phasenoise pilot is specific to one terminal and used by the terminal deviceto perform phase noise estimation. The cell-level phase noise pilot isspecific to a plurality of terminals and used by terminals in a physicalcell to perform phase noise estimation.

The cell-level phase noise pilot is carried in a downlink resource unit,and the user-level phase noise pilot may be carried in an uplinkresource unit or a downlink resource unit. Both the cell-level phasenoise pilot and the user-level phase noise pilot may be used. Forexample, the cell-level phase noise pilot is used in a downlink, and theuser-level phase noise pilot is used in an uplink.

Further, for downlink data transmission, only one of the cell-levelphase noise pilot and the user-level phase noise pilot is used.Specifically, when a quantity of terminals in a preset range is lessthan a first preset quantity, the user-level phase noise pilot is used;or when a quantity of terminals in a preset range is greater than asecond preset quantity, the cell-level phase noise pilot is used. Thefirst preset quantity may be equal to the second preset quantity, or thefirst preset quantity may be less than the second preset quantity. Thepreset range may be a range covered by a physical cell.

In this embodiment, a system may use different phase noise pilots indifferent scenarios, to achieve a balance between overheads andperformance.

The foregoing describes the solutions provided in the embodiments ofthis application mainly from a perspective of interaction between thebase station and the terminal. It may be understood that, to implementthe foregoing functions, the base station and the terminal include ahardware structure and/or a software module for performing correspondingfunctions. With reference to units and algorithm steps in the examplesdescribed in the disclosed embodiments of this application, theembodiments of this application may be implemented in a form of hardwareor a combination of hardware and computer software. Whether a functionis performed by hardware or by computer software driving hardwaredepends on particular applications and design constraint conditions ofthe technical solutions. Persons skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of the technical solutions in the embodiments ofthis application.

In the embodiments of this application, the base station and theterminal may be divided into functional units based on the foregoingmethod examples. For example, the functional units may be obtainedthrough division based on corresponding functions, or two or morefunctions may be integrated into one processing unit. The integratedunit may be implemented in a form of hardware, or may be implemented ina form of a software functional unit. It should be noted that, in theembodiments of this application, unit division is an example, and ismerely a logical function division. In actual implementation, there maybe another division manner.

When an integrated unit is used, FIG. 9 shows a possible schematicstructural diagram of a related terminal according to the foregoingembodiments. A terminal 100 includes a processing unit 12 and acommunications unit 13. The processing unit 12 is configured to controland manage an action of the terminal. For example, the processing unit12 is configured to support the terminal in performing the processesS301 and S302 in FIG. 3 , the processes S403 and S404 in FIG. 4 , theprocesses S502 and S503 in FIG. 5 , the process S602 in FIG. 6 , theprocess S701 in FIG. 7 , and the process S801 in FIG. 8 and/or anotherprocess of a technology described in this specification. Thecommunications unit 13 is configured to support communication betweenthe terminal and a base station. The terminal may further include astorage unit 11, configured to store program code and data of theterminal.

The processing unit 12 may be a processor or a controller, for example,a central processing unit (CPU), a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field programmable gate array (FPGA) or another programmablelogic component, a transistor logic component, a hardware component, orany combination thereof. The processing unit 12 may implement or performvarious example logical blocks, modules, and circuits that are describedwith reference to the disclosed content of this application. Theprocessor may also be a combination for implementing computingfunctions, for example, a combination of one or more microprocessors anda combination of a DSP and a microprocessor. The communications unit 13is a transceiver, a transceiver circuit, or the like. The storage unit11 may be a memory.

When the processing unit 12 is a processor, the communications unit 13includes a transmitter and/or a receiver, and the storage unit 11 is amemory, the related terminal in this embodiment of this application maybe the terminal shown in FIG. 10 .

FIG. 10 shows a simplified schematic diagram of a possible designstructure of a related terminal according to an embodiment of thisapplication. A terminal 200 includes a transmitter 21, a receiver 22,and a processor 23. The processor 23 may also be a controller, and isrepresented as a “controller/processor 23” in FIG. 10 . Optionally, theterminal 200 may further include a modem processor 25. The modemprocessor 25 may include an encoder 26, a modulator 27, a decoder 28,and a demodulator 29.

In an example, the transmitter 21 adjusts (for example, performs analogconversion, filtering, amplification, and up-conversion) output samplingand generates an uplink signal. The uplink signal is transmitted to thebase station in the foregoing embodiments through an antenna. In adownlink, the antenna receives a downlink signal transmitted by the basestation in the foregoing embodiments. The receiver 22 adjusts (forexample, performs filtering, amplification, down-conversion, anddigitization) a signal received from the antenna and provides inputsampling. In the modem processor 25, the encoder 26 receives servicedata and a signaling message that are to be sent in an uplink, andprocesses the service data and the signaling message (for example,performs formatting, encoding, and interleaving). The modulator 27further processes (for example, performs symbol mapping and modulation)encoded service data and an encoded signaling message, and providesoutput sampling. The demodulator 29 processes (for example, performsdemodulation) the input sampling, and provides symbol estimation. Thedecoder 28 processes (for example, performs de-interleaving anddecoding) the symbol estimation, and provides decoded data and a decodedsignaling message that are to be sent to the terminal 200. The encoder26, the modulator 27, the demodulator 29, and the decoder 28 may beimplemented by the combined modem processor 25. The units performprocessing based on a radio access technology (for example, accesstechnologies of LTE and another evolved system) used in a radio accessnetwork. It should be noted that, when the terminal 200 does not includethe modem processor 25, the foregoing functions of the modem processor25 may also be completed by the processor 23.

The processor 23 controls and manages an action of the terminal 200, andis configured to execute a processing process performed by the terminal200 in the foregoing embodiments of this application. For example, theprocessor 23 is further configured to perform the processes S301 andS302 in FIG. 3 , the processes S403 and S404 in FIG. 4 , the processesS502 and S503 in FIG. 5 , the process S602 in FIG. 6 , the process S701in FIG. 7 , and the process S801 in FIG. 8 and/or another process of thetechnical solutions described in this application.

Further, the terminal 200 may further include a memory 24. The memory 24is configured to store program code and data of the terminal 200.

When an integrated unit is used, FIG. 11 shows a possible schematicstructural diagram of a related base station according to the foregoingembodiments. A base station 300 includes a processing unit 32 and acommunications unit 33. The processing unit 32 is configured to controland manage an action of the base station. For example, the processingunit 32 is configured to support the base station in performing theprocesses S401 to S403 in FIG. 4 , the processes S501, S503, and S504 inFIG. 5 , the process S601 in FIG. 6 , the process S702 in FIG. 7 , andthe process S802 in FIG. 8 and/or another process of a technologydescribed in this specification. The communications unit 33 isconfigured to support communication between the base station and aterminal. In addition, the communications unit 33 may further supportcommunication between the base station and another network entity, forexample, a mobility management entity (MME) and a serving gateway (SGW).The base station may further include a storage unit 31, configured tostore program code and data of the base station.

The processing unit 32 may be a processor or a controller, for example,a central processing unit (CPU), a general-purpose processor, a digitalsignal processor (DSP), an application-specific integrated circuit(ASIC), a field programmable gate array (FPGA) or another programmablelogic component, a transistor logic component, a hardware component, orany combination thereof. The processing unit 32 may implement or performvarious example logical blocks, modules, and circuits that are describedwith reference to the disclosed content of this application. Theprocessor may also be a combination for implementing computingfunctions, for example, a combination of one or more microprocessors anda combination of a DSP and a microprocessor. The communications unit 33may include a transceiver, a transceiver circuit, a communicationsinterface, and the like. The storage unit 31 may be a memory.

When the processing unit 32 is a processor, the communications unit 33includes a transmitter and/or a receiver, and the storage unit 31 is amemory, the related base station in this embodiment of this applicationmay be a base station shown in FIG. 12 . The transmitter and/or thereceiver may be represented as a “transmitter/receiver”.

FIG. 12 shows another possible schematic structural diagram of a relatedbase station according to an embodiment of this application.

A base station 400 includes a transmitter/receiver 41 and a processor42. The processor 42 may also be a controller, and is represented as a“controller/processor 42” in FIG. 12 . The transmitter/receiver 41 isconfigured to support the base station in sending and receivinginformation to/from the terminal in the foregoing embodiments, andsupport radio communication between the terminal and another terminal.The processor 42 performs various functions of communicating with theterminal. In an uplink, an uplink signal from the terminal is receivedvia an antenna, and is demodulated by the receiver 41 (for example, ahighfrequency signal is demodulated to obtain a baseband signal).Further, the processor 42 performs processing to restore service dataand signaling information sent by the terminal. In a downlink, servicedata and a signaling message are processed by the processor 42, and aremodulated by the transmitter 41 (for example, a baseband signal ismodulated to obtain a high-frequency signal) to generate a downlinksignal. The downlink signal is transmitted to the terminal via theantenna. It should be noted that the foregoing demodulation ormodulation function may also be completed by the processor 42. Forexample, the processor 42 is further configured to perform the processesS401 to S403 in FIG. 4 , the processes S501, S503, and S504 in FIG. 5 ,the process S601 in FIG. 6 , the process S702 in FIG. 7 , and theprocess S802 in FIG. 8 and/or another process of the technical solutiondescribed in this application.

Further, the base station 400 may further include a memory 43. Thememory 43 is configured to store program code and data of the basestation 40. In addition, the base station may further include acommunications interface 44. The communications interface 44 isconfigured to support communication between the base station and anothernetwork entity (for example, a network device in a core network). Forexample, in an LTE system, the communications interface 44 may be anS1-U interface, and is configured to support communication between thebase station and an SGW; or the communications interface 44 may be anS1-MME interface, and is configured to support communication between thebase station and an MME.

It may be understood that FIG. 12 shows only a simplified design of thebase station 400. In actual application, the base station 400 mayinclude any quantity of transmitters, receivers, processors,controllers, memories, communications interfaces, and the like. All basestations that can implement this embodiment of this application fallwithin the protection scope of this embodiment of this application.

Methods or algorithm steps described in combination with the contentdisclosed in the embodiments of this application may be implemented byhardware, or may be implemented by a processor by executing a softwareinstruction. The software instruction may include a correspondingsoftware module. The software module may be stored in a random accessmemory (RAM), a flash memory, a read-only memory (ROM), an erasableprogrammable read only memory (EPROM), an electrically erasableprogrammable read only memory (EEPROM), a register, a hard disk, aremovable hard disk, a compact disc read-only memory (CD-ROM), or anyother form of storage medium well-known in the art. For example, astorage medium is coupled to the processor, so that the processor canread information from the storage medium or write information into thestorage medium. Certainly, the storage medium may be a component of theprocessor. The processor and the storage medium may be located in theASIC. In addition, the ASIC may be located in a base station or aterminal. Certainly, the processor and the storage medium may exist in abase station or a terminal as discrete components.

Persons skilled in the art should be aware that in the foregoing one ormore examples, functions described in the embodiments of thisapplication may be implemented by hardware, software, firmware, or anycombination thereof. When the functions are implemented by software, thefunctions may be stored in a computer-readable medium or transmitted asone or more instructions or code in the computer-readable medium. Thecomputer-readable medium includes a computer storage medium and acommunications medium, where the communications medium includes anymedium that enables a computer program to be transmitted from one placeto another. The storage medium may be any available medium accessible toa general-purpose or dedicated computer.

Persons of ordinary skill in the art may understand that all or some ofthe steps of the method embodiments may be implemented by a programinstructing relevant hardware. The program may be stored in acomputer-readable storage medium. When the program runs, the steps ofthe method embodiments are performed. The foregoing storage mediumincludes: any medium that can store program code, such as a ROM, a RAM,a magnetic disk, or an optical disc.

Finally, it should be noted that the foregoing embodiments are merelyintended for describing the technical solutions of this applicationother than limiting this application. Although this application isdescribed in detail with reference to the foregoing embodiments, personsof ordinary skill in the art should understand that they may still makemodifications to the technical solutions described in the foregoingembodiments or make equivalent replacements to some or all technicalfeatures thereof, without departing from the scope of the technicalsolutions of the embodiments of this application.

What is claimed is:
 1. A method comprising: obtaining downlink controlinformation (DCI) comprising information about a modulation order and aquantity of scheduled resource blocks; and performing datacommunications in one or more of the scheduled resource blocks accordingto the modulation order, wherein information carried in the one or moreof the scheduled resource blocks does not include any phase noisereference signal, based on the modulation order being less than a presetmodulation order or the quantity of the scheduled blocks being less thana preset quantity, and wherein the information carried in the one ormore of the scheduled resource blocks includes at least one phase noisereference signal based on the modulation order being greater than orequal to the preset modulation order and the quantity of the scheduledresource blocks being greater than or equal to the preset quantity. 2.The method according to claim 1, wherein based on the reference signalbeing a downlink reference signal, performing the data communicationcomprises receiving the information carried in the one or more of thescheduled resource blocks; and based on the reference signal being anuplink reference signal, performing the data communication comprisestransmitting the information carried in the one or more of the scheduledresource blocks.
 3. The method according to claim 1, wherein thereference signal is used in a high frequency scenario.
 4. A methodcomprising: sending downlink control information (DCI) comprisinginformation about a modulation order and a quantity of scheduledresource blocks; and performing data communication in one or more of thescheduled resource blocks according to the modulation order, whereininformation carried in the one or more of the scheduled resource blocksdoes not include any phase noise reference signal, based on a modulationorder being less than a preset modulation order or the quantity of thescheduled blocks being less than a preset quantity, and wherein theinformation carried in the one or more of the scheduled resource blocksincludes at least one phase noise reference signal based on themodulation order being greater than or equal to the preset modulationorder and the quantity of the scheduled resource blocks being greaterthan or equal to a preset quantity.
 5. The method according to claim 4,wherein based on the reference signal being a downlink reference signal,performing the data communication comprises transmitting the informationcarried in the one or more of the scheduled resource blocks; and basedon the reference signal being an uplink reference signal, performing thedata communication comprises receiving the information carried in theone or more of the scheduled resource blocks.
 6. The method according toclaim 4, wherein the reference signal is used in a high frequencyscenario.
 7. An apparatus comprising at least one processor and atransceiver, wherein the at least one processor is configured to:obtain, through the transceiver, downlink control information (DCI)comprising information about a modulation order and a quantity ofscheduled resource blocks; and perform, through the transceiver, thedata communication in one or more of the scheduled resource blocksaccording to the modulation order, wherein information carried in theone or more of the scheduled resource blocks does not include any phasenoise reference signal, based on the modulation order being less than apreset modulation order or the quantity of the scheduled blocks beingless than a preset quantity, and wherein the information carried in theone or more of the scheduled resource blocks includes at least one phasenoise reference signal, based on the modulation order being greater thanor equal to the preset modulation order and the quantity of thescheduled resource blocks being greater than or equal to a presetquantity.
 8. The apparatus according to claim 7, wherein based on thereference signal being a downlink reference signal during the datacommunication, the transceiver is configured to receive the informationcarried in the one or more of the scheduled resource blocks; and basedon the reference signal being an uplink reference signal during the datacommunication, the transceiver is configured to transmit the informationcarried in the one or more of the scheduled resource blocks.
 9. Theapparatus according to claim 7, wherein the reference signal is used ina high frequency scenario.
 10. An apparatus comprising at least oneprocessor and a transceiver, wherein the at least one processor isconfigured to: send, through the transceiver, downlink controlinformation (DCI) comprising information about a modulation order and aquantity of scheduled resource blocks; and perform, through thetransceiver, data communication in one or more of the scheduled resourceblocks according to the modulation order, wherein information carried inthe one or more of the scheduled resource blocks does not include anyphase noise reference signal, based on the modulation order being lessthan a preset modulation order or the quantity of the scheduled blocksbeing less than a preset quantity, and wherein the information carriedin the one or more of the scheduled resource blocks includes at leastone phase noise reference signal, based on the modulation order beinggreater than or equal to the preset modulation order and the quantity ofthe scheduled resource blocks being greater than or equal to a presetquantity.
 11. The apparatus according to claim 10, wherein based on thereference signal being a downlink reference signal during the datacommunication, the transceiver is configured to cooperate with theprocessor to transmit the information carried in the one or more of thescheduled resource blocks; and based on the reference signal being anuplink reference signal during the data communication, the transceiveris configured to cooperate with the processor to receive the informationcarried in the one or more of the scheduled resource blocks.
 12. Theapparatus according to claim 10, wherein the reference signal is used ina high frequency scenario.
 13. A method comprising: sending, by anaccess network device, downlink control information (DCI) comprisinginformation about a modulation order and a quantity of scheduledresource blocks; and obtaining, by a terminal device, the DCI;performing data communications between the access network device and theterminal device in one or more of the scheduled resource blocksaccording to the modulation order, wherein information carried in theone or more of the scheduled resource blocks does not include any phasenoise reference signal, based on the modulation order being less than apreset modulation order or the quantity of the scheduled blocks beingless than a preset quantity, and wherein the information carried in theone or more of the scheduled resource blocks includes at least one phasenoise reference signal, based on the modulation order being greater thanor equal to the preset modulation order and the quantity of thescheduled resource blocks being greater than or equal to the presetquantity.
 14. The method according to claim 13, wherein each of thepreset modulation order and the preset quantity is prestored in theterminal device and the access network or obtained by the terminaldevice from the access network device.
 15. The method according to claim13, wherein based on the reference signal being a downlink referencesignal, performing the data communication comprises: transmitting, bythe access network device, the information carried in the one or more ofthe scheduled resource blocks; and receiving, by the terminal device,the information; and based on the reference signal being an uplinkreference signal, performing the data communication comprises:transmitting, by the terminal device, the information carried in the oneor more of the scheduled resource blocks; receiving, by the accessnetwork device, the information.
 16. The method according to claim 13,wherein the reference signal is used in a high frequency scenario.